Straightedge glass plate beveling and edging machine



June 10, 1 w. A. REASER arm. 2,600,127

STR AIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 13, 1949 12 Sheets-Sheet 1 m/ was '6 IN VEN TORS: Wlliam Alleaser, ElmerA. Ztem,

John M. Christin an.

June 0, 1 w. A. REASER ETAL 2,

STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 13. 1949 12 Sheets-Sheet 2 ATTYS.

June 1952 WA. REASER ETAL I 2,600,127

S'IfRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 15. 1949 v v v v 12 Sheets-Sheet s INVENTORY: William ZLRea-se r, Elmer A. Ziems,

John Mi'hristmaw.

JTTYS'.

June 10, 1952 w REASER ETAL 2,600,127

STRAIGHTEDGE GLASS PLATE BEVEL ING AND EDGING MACHINE Filed April 13. 1949 12 Sheets-Sheet 4 INVENTORS:

VVilliam A.Reaser, Elmerfl. Zierns,

Jain; M l iw'iittnan AT TYS.

June 10, 1952 w. A. REASER ETAL STRAIGHTEDGE GLASS PLATE BEVELI NG AND EDGING MACHINE l2 Sheets-Sheet 5 Filed April 13, 1949 at mm QHE ATTYI".

J n 0, 1952 w. A. REASER ETAL STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 15, 1949 12 Sheets-Sheet 6 r June 10, 1 w. A. REASER ETAL STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE l2 Sheets-Sheet 7 Filed April 15, 1949 Lw/ i0 INVENTORJ. A.R ea-ser-,

William mer John.

1%.. Zlems,

m T A STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 15, 1949 W. A. REASER EIAL June 10, 1952 12 Sheets-Sheet 8 June 10, 1952 w. A. REASER arm. 2,600,127

STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 13. 1949 12 Sheets-Sheet 9 INVENTORY. William. A. Reaser', Elmer J1. Ziems,

John M. Christ-man A TT Y8.

June 10, 1952 w. A. REASER EI'AL 2, 0

STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 13, 1949 12 Sheets-Sheet 1o INVENTORJ mllinm A-Reaser',

lmer A. Ziems, Jaha- Mchrllii'man.

ATTYJ.

June 10, 1952 w. A. REASER EI'AL STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 13, 1949 12 Sheets-Sheet l1 TM. mHHflu \N H H I M u 1 5 N$ %\\i J N mfifl n m ig .AAM. p aen PM m5 w mNE June 10, 1952 w, REASER ETAL 2,600,127

STRAIGHTEDGE GLASS PLATE BEVELING AND EDGING MACHINE Filed April 15, 1949 12 Sheets-Sheet 12 nuns 1 TIE-2E1- mlliam A. Rta-scr', Elmer A. 21:01:,

John M. Chrisfina-w.

Patented June 10,1952

STATE-S 2,600,127 STRAIGHTEDGE; eLAss PLATEAEVEIIING AND ED GI-NG MAGHI-NE Ohio 6 Claims.-

' Thisinventioxr felates'td maehines" and niethdds fer grinding bevels" on the dgesfj 6f 'g1 e3ssplates" and. elfgifig the same, and fiarticulejrly t6 machines" of this cfass for iiridhig plates having straight edges.

Due to the glass prate Heing beveled verying' in thickness as muchas' ohethirtys'e'corid of an inch end else" due to a; plurality 61 glass plates, when pl aced together on a; wdrk table for successive beveling, being of difirer'lt thicknesses, it is" extremely difilcult, the use of machines 61 this character; to ggi'nd uhifofm b'evels' having straight as distinguished f rom' wavy edge lines; If the gla'ss" b'eihg" gr'o'un'd is ufletfeh thickness; which is usually the" ease, 61'' if a pmram'y of clamped pieces of glass to-he sheee'ssively gr'ciuhd' areuneveh' in thickness; the line termed by the ft'ceof the-bevel andbythefface of the glass will not be straight and parallel" with the edg' e-of the glass if gri ding d'cin' 611 top of glass. As these vari etibns thicknessefei'ncr'eased many timeson thelevel lihe, iti'sappa-rent that glass bevel termed by present fiiethbds and machines, so far as weare mere has" a; very fidh -uhi fdrniwavy appearafice 'I he rimary object of the presem: ifiYei-itien 1' s' the provision of an apparatus forgrindinged'ges' and. bevelsf 0H glass plates, 95nd pel' tiular' ly straight edge plates; whereby the variation in thickness of the plates will nbt affect the truene's's ofi the grbuncl bevel and willcause" the edges of thebevel to he liai'llel amstraight} and all bevels wi-llbe ofiuniform'width;

Ith'si fbun'd; in' practice that this fesultf can be accemplished ina; simple and-emcient manner by clampihg the plate or platesto be beveled to a' fiat Stl'ifiale' a;- maimento hold the Contacting plate sideperfectly fiat to such sur-felce; with the edge: to be beveled proj ectihgl therefrom; and then applying the heveling action tosaidside. The glassmustbe held with asufiiciently unyielding force t0 withstand'the great pressure caused by the: grindingw'heetwhen cutting, and the clampmglmeans-mustbehea vy-enough to absorb any vibratibn; caused' by. the-grinding acti'on. The" clam in ressure should be" uififOfiYllY distiib utedfovet' the glass whether" uri pieeeofa nuz'n befot'pieces ar'beifig g'fbl'lfid. 7

Other objects and advantages of theinvention will be aipparefit from" thefollowifig detailed de"-' 50' scri'ptioh and from the accompanying drawings; in'which:

Fig; 1 i's a; perspective frbnt elevation of a: machine embodying the ifiVBIiti'cjfilObkihg alt the newer: ti'fizi's'rffissidn end theredf, with" Iia'rts 65 ward 7 persziectivev w f 01 gt ith f eets rtv in loweiea a; bevel-gr side and end elevations thereof, and Fig. 28 is a diagram of the electric wiring for the machine.

Referring to the drawings, I designates the body frame of the machine and this, as best shown in Figs. 2 and 4, is of hollow skeleton form substantially rectangular in cross-section with an open top and of considerable length. Front and rear rails 2 and 3 are mounted, respectively, on the front and rear top edge portions of the frame and support a carriage 4 for forward and backward movements lengthwise of the frame. The frame rail 2 comprises a ground cylindrical bar that is straddled by a series of saddles 5 on the under side of the carriage at its front edge portion and which serve to support the carriage and guide its movement. The rear rail 3 is engaged by anti-friction rollers 6 on the rear edge portion of the carriage. This form of guide and support for the carriage requires less accuracy when machining the base frame and eliminates danger of galling.

A plurality of brackets 8 (Fig. 4) project forward in longitudinally spaced relation from the front side of the frame I intermediate its ends, and these brackets support and are connected by a heavy plate or beam-like structure 9, which in turn supports the rear or inner edge of a work-supporting table ID in forwardly spaced relation to the carriage 4. The table I0, which is perfectly flat on top for supporting the glass plates A to be beveled, is mounted at its front or outer edge by legs II resting on adjustable screw feet or other suitable adjustable supports. The work plates A are placed on the table I with a straight edge thereof to be beveled projected beyond the inner edge of the table slightly more than the width of the bevel, and these plates are firmly clamped to the table by a clamping head I2, as best shown in Fig. 10. This head and its manner of operation are best shown in Figs. 8 to 13.

The head I2 includes a top beam-like member I3 extending crosswise over the inner edge of the table and guided at its ends in vertical grooves I4 provided in standards I5 rising from the, beam structure 9 on the body frame I at each end of the table. The member I3 is provided at its lower edge with a pressure foot I6 projecting at its side edges beyond the sides of the member I3 and loosely carrying a plurality of pressure shoes II. These shoes are of rectangular form in horizontal section and are placed in side abutting relation lengthwise of the clamp to provide a substantially continuous pressure member for engaging the surface of the glass plates A in opposition to the table. Each shoe I! is provided in its top with a cross-recess I8 which receives and is of greater depth than the pressure foot I6. The top side edge walls of the recess engage over the edges of the foot I6 to limit the outward movement of one relative to the other. A yielding cushion means I9 is disposed within the recesses I8 of the several pressure shoes I! and receives the thrust of the pressure foot I6 to equalize its pressure on the. several shoes and at the same time permit relative movements thereof to compensate for any variation in thickness of a glass plate or plates being clamped. The cushion I9 comprisesa hose-like member closed at its ends and partially filled with a non-compressible fluid so that it will automatically adjust itself to different positions of the pressure shoes without variation in the pressure applied thereto. The shoesIl have their glass coacting bottom sur- 4 faces faced with canvas or other suitable material I'm to prevent marring of the glass.

Mounted on the upper end of each standard I5 isa vertical cylinder containing a piston 2| that is connected by a rod 22 to the respective end of the clamping head beam I3 so that movements of the pistons in the cylinders will raise and lower the clamping head I2. Air under pressure is admitted to the cylinders at one side or the other of the pistons from a supply pipe 24, a control valve means 25 and distributing pipes 26 (Fig. 3). The control means is of any well-known type suitable for directing the flow of air under pressure to both cylinders at either side of the pistons and for relieving the pressure in the side opposed to that to which the air is being admitted. This means need not, therefore, be described in detail. The air supply is also through a common form of filter and pressure gauge unit 21. A shaft 30 is disposed at one side of the clamping head I2, being mounted at its ends in the standards I5, and has pinions 3I in engagement with vertical racks 32 on the respective end portions of the body member I3 of said head to cause the two ends of the head to have uniform raising and lowering movements.

At the inner side of the table In, below its top edge, is mounted a normally operable gauge and. stop means for properly positioning the front edge of the glass plates A for beveling. This means, which is best shown in Figs. 8, 9, 10 and 11, includes a rockshaft 35 parallel to the front table edge and mounted in bearing brackets 36 projecting from the table below the path of movement of the beveling means hereinafter to be described. On one end of said shaft is mounted an operating arm 31 having a manually releasable spring catch 38 at its outer end for engagement with notches 39 in a segment 49, fixed to the table, to hold the arm in different adjusted positions. A plurality of gauge arms M are mounted on the shaft 35 intermediate the bearing brackets 36 and each has a gauge pad 42 at its outer end. A lowering of the arm 31 causes the pads 42 to swing up into gauging position for the front edges of the work plates when placed on the table, as shown in Fig. 8. A stop 43 on the upper edge portion of the segment stands in the path of movement of the arms 31 and limits such movement.

The carriage 4, which is mounted for reciprocatory movements on the base rails 2 and 3 in parallel relation to the inner table edge, has a plurality of work abrading units mounted thereon, in the present instance four in number and designated B, C, D and E in Fig. 6. Each of these units (Figs. 4 and '7) comprises a base 45 mounted in a respective guideway on the carriage 4 for adjusting movements in a line at right angles to the carriage movement, such adjustment being accomplished by turning a screw shaft 46 in engagement with the respective unit. A hand wheel 41 on the rear end of the shaft is provided with a peripheral graduation 48 with which a pointer 49 on the carriage registers. The base 45 is locked in adjusted position by hand clamping screws 58. On the top of each base 45 near its forward or inner end is mounted a frame block 5| for rocking adjustment on a shaft 52 in a vertical plane'at right angles to the carriage movement. Such adjustment is effected by the turning of a screw 53 on the base portion of the block in thrust engagement with the base 45, and the adjustment is maintained by a screw 54 on the deceit-27*- block having clampingengagement with aslotted arm- 55- on the base.

' A respective electric motor 5!- (sometimes identified with the particular unit by the inclusion of the designating letter for such unit) is mounted on the rear side of each frame block 5-! with its shaft axis upright. The motor case, in thepresent instance, has a mounting plate 53 fixedly attached to its inner side and pivoted for horizontal rocking adjustment to a carrying member 59 that is mounted for vertical adjustment on the'rear side of the block 5!. The plate 58 is rockingly adjusted by screws 6%, at opposite sides of its axis bearing against the member 59. The vertical adjustment of the member 59- on the block is effected by the turning of anassociated hand-screw 61- that is journaled a bracket 62 s on the upper end of said member and has its lower end threaded in the top of the block. The member 59 is rigidly held in adjusted position by screws 63 extending through slots 6d in block flanges and threading into the member 59'. Each screw [H is provided with a hand wheel 65. The motor shaft carries one or more pulleys $6 at its upper end for drive belts 61, for the associated element. A cover 68 is disposed over each unit.

On the front or inner side of each frame block El is mounted a bearing head 18- for vertical and rocking adjustment, and in this is mounted a verti-cal-ly disposed shaft ll carrying an abrading wheel T2 at its lower end and which, for the purpose of identification with its particular unit, is given the designation B, 0, Band E, corresponding to the designation ofthe particular unit. The shaft H at its upper end carries pulleys T3 with which the respective drive belts 6T connect. In the present instance, the head 10- for each unit is provided at its inner side relative to the frame block H with oppositely projecting wings it that are attached by screws '15 to a verticallyadjust ingj member it that is attached to the respective block" 51, and the head is vertically adjustable in the same manner as the member 59 that carries the motor. The hand adjusting screw for the member 18- is designated 11. The bearing head '20 has pivotal connection with the member I6, as indicated at 73 (Fig. '7') to permit transverse rocking adjustment of the head relative to the member. In addition to the screws 15, the head T3 is held in adjusted clamped relationto the frame block 5!- by bolts its that project through the flanges it, member it and the flange portions of the block. For the purpose of said pivotal adjustment of the head it, the bolts or screws and 15a. pass through respective slots 19 in the flanges it, such slots being concentric to: theaxis of the "pivot it.

The several abrading units B, C, D and E, are mounted in successive order from right to left (Figs. 1, 5 and 6) lengthwise of the carriage 4 and atthe left side of the table It when: the carriage is in its normal at-rest or starting position. First in the order of engagement with the work is the rough beveling'wheel TZ-B; then: the semi-finishing wheel it-C; then the finishing wheel 12-1), and last the edging wheel T2-E so: that as the carriage moves. from leftv to right, or traverses its bevel-forming stroke, the. abrading wheels: successively act to perform their respective operations on the under side of the. exposed. edge portions of the glass plates. A that overhang the inner table edge. The wheels. IZ-B, 112-C and l2-D have their topmarginal edge. surfaces beveled as indicated. at b,. so as. to impart the depassthereu-nder, as shown in Fig. 7. Itis preferable to laterally tilt the head to relative to the carrying blocks 5|, so that the line of en: gagement of the wheel with the glass is at one: side of a line that is at right angles to the edge line of the glass and diametrical to the wheel axis, as illustrated in Fig. '7. This causes the: abrad-ing lines of the glass to be crosswise instead oflengthwise of the be'vehthus enabling them to be more readily and effectively wiped out by the: finishing wheels. An adjustment of each abrading unit about its shaft 52 facilitates adjustment of the wheel to suit the inclination and width of the bevel cut desired, and this aided by a vertical and transverse Swinging adjustment of the bearing head it relative to the block 5 I.

The feed means for the carriage 4 comprises a long lead screw 8'6 passing through a feed nut 81 on the under side of the carriage and being journaled at its power end in the adjacent Wall of a housing 52 located at the right end of the base frame I looking at the rear as in Fig. 2. The screw extends nearly the full length of the base frame intermediate the carriage rails 2 and 3 and has its outer or left end (Fig. 2) journa-Ied in two longitudinally spaced bearings 83ancl 84. By using two bearings at the end of the lead screw the sag oi the screw, due to its length and weight, can be considerably reduced over what it would be if only one bearing were used at its outer end. If the bearings are in line, it is found that the sag is'reduced by about one-half, where-- as if only one bearing is slightly lowered relative to the-other, the sag will be reduced to about-onc quarter of what it would be if only one bearing were used.

The power and transmission means for the lead. screw islocated in the housing 82 and comprises, in the present instance, two electric motors 85, 86', driving respective shafts 81 and 88 of a planetary transmission gearing (Figs. 22, 23, 24). This transmission includes a case 9!!- rotatable about the aligned axes of the drive shaft 81 and lead screw 88 and having a circumferential ring'gear. 9i" fixed thereto. The shaft 87 is journaled at its outer end in a bracket arm 92 and. projects. centrally into the. case through a bearing'in. its side and has an end bearing in the inner end of a sleeve 93 that is fixedlymounted on the power end of the lead screw 80. A sun gear 941s. fixed to the shaft 81 within the case and meshes withv a series of planetary gears 95 mounted therearound. These gears are carried by respective shafts 9t journaled in a ring; or spider 91 that in turn is journaled on they inner: end portion of. the sleeve 93. Each. shaft 96 is j'curnaled atone end in. the respective side of the case 98 and. carries a pinion as in mesh with. a gear 99 fixed.- to the sleeve 93. Power from the. motor as. to the shaft 81 is through. a belt and pulley con-- nection I88.

It is thus apparent that when the case 9d is stationary. poweristransmitted through the. shaft 8?, gears 9d and 95, shafts: 9t and gears 98' and. 99. to the lead screw; Forslower' speed; ofthe lead screw, poweris transmitted from the. motor S6 to the shaft 58 through a belt and. pinion. connection ml. The shaft 88: has bearings in a bracket Hi2 and carries a gear H13 in. mesh with the ring gear St. A driving of the gear I03 causes the case 90 to turn at apredetermined' speed and to carry the planetary shafts; 9b with their gear around the axessof: the shafts siredv bevel to the edges. of the glass'plates. as they 7'5; and 8!- and thus reduce the-speed.- or imiting;

of the lead screw 80 from the shaft 81. In prac-' tice, the shaft 83 is driven in only one direction by its motor 86, while the motor 85 is of the reversible type and drives the shaft 81 in one direction or the other, depending on the desired direction of movement of the carriage 4. In Fig. 1, I04, I04, represent standard type plug-in switches in connection with the motors 85, 86, so as to permit a speed control range for the carriage movements.

The coolant for the grinding wheels is pumped from a sump chamber I88 by an electric pump I09 and directed to the several grinding wheels through a suitable distributing system indicated III! in Fig. 2. This system has two nozzles II I and H2 (Figs. 16, 1'7, 18) associated with each of the bevel grinding and finishing wheels 12-B, 'I2C and 12-D (Fig. the nozzle III extending over the bevel surface adjacent to the point of engagement with the work and being perforated to direct a plurality of small streams down against the wheel. The other nozzle directs a single stream over the bevel surface of the wheel in advance of its engagement with the work. A nozzle II3 (Figs. 19, 20 and 21) is associated with the work edging wheel 12-E and directs a stream of coolant against the edging groove tangentially thereof and toward the work-engaging point, as shown in Figs. 19 and 20. The coolant, together with the removed grit from the wheels, drains into a settling tank II5 (Figs. 4, 5 and 6) and is discharged therefrom into a tank H6 in one end of the base frame I and from it into a rear settling tank II1. This tank has a plurality of successive settling compartments I I 8 along one side and the coolant flows from one to the other of these over the dividing partitions II9. At the far end the flow is over a low wall partition at I20 into the long compartment I08 from which the coolant pump I99 takes its supply for the cooling system. The tank II5 is broad at both ends of the table I 9 and narrow between the inner edge of the table and the top edge portion of the base frame I, and is supported by the frame brackets 8 and front frame plate 9. In Figs. 14 and 15 is shown a dressing means I25 for the bevel grinding wheels. This means includes a vertically disposed bracket plate I26 provided at its inner edge with a foot plate I28 that seats against a flat dovetail male part I29 on the front side of the respective head 13 and has at one edge an undercut flange that engages under one edge of said part. The other edge of the plate I28 is provided with a screw-operated clamp I30 engaging under the other edge of said dovetail part and serving to hold the bracket in adjusted relation to the head 10. A plate I3I is mounted for vertical adjustment on a side of the plate I26 in a way provided thereon and is engaged by an adjusting screw I32 carried by the part I26, whereby a turning of the screw will vertically adjust the plate I3 I. A hearing sleeve I33 has a fiat bearing at one side against the plate I3! and is pivoted thereto at I34 (Fig. 15) for vertical swinging adjustment and is clamped in adjusted position by screws I35 extending through arcuate slots I36 in'flanges on the sleeve I33 for movements toward and away from the axis of the associated grinding wheel. A bar I31 is mounted for reciprocatory movement in the sleeve I33. A lever I33 connects bar and sleeve and is operable to impart axial movements to the bar. A trimming wheel I39 is carried at the inner end of the bar I31 for free rotary movements in a plane normal to the bar axis and is adapted to have peripheral trimming engagement with the bevel grinding surface of the associated grinding wheel. The trimming wheel may be moved inward and outward on the grinding surface of the abrading wheel by axial movements of the carrying bar and can be properly adjusted to said grinding surface by vertical adjustment of the plate I3I and pivotal adjustment of the bearing sleeve I33. This trimming means can be used in connection with any bearing head 10 and removed entirely therefrom when the trimming has been effected.

A trimming means I40 (Figs. 5, 6, 25, 26 and 27) for the edging wheel 12-E is mounted on a bracket I4I secured to the outer side of the standard I5 at the right end of the table I0. This means includes a base plate I42 adjustable lengthwise of the bracket in the plane of movement of the carriage 4 by a hand screw I43 and has spaced bars I44 and I45 mounted crosswise thereon, and is adjustably clamped thereto by bolts I46 passing through slots I41 in the bars. Fine lengthwise adjustment of each bar is accomplished by screws I48. An arbor I49, carrying a trimming wheel I50 for the peripheral edging groove 9, is attached at one end to the bar I44 for universal swinging movements andits other end is provided with a gauge pinI5I which projects from the arbor in the plane of rotation of the trimming wheel and bears against a curved surface of a template I52 rising from the plate I42. The pin I5I is threaded in the arbor end for axial adjustment and has a head or handgrip I53 at its outer end. A hand knob I54 is provided on the free end of the arbor to facilitate hand control of its movements.

The control system for the various electric motors of the apparatus is illustrated diagrammatically in Fig. 28 and includes a set of controls I60 (Fig. 1) for the carriage movements conveniently located above the left side of the work table, and a second set of controls I6I (Fig. l) for the several grinding wheel motors 51, the coolant pump motor I09 and the speed control plugging switches I94, I04, of the two motors 85 and 86.

Referring to the control set I60, the button It controls the carriage feed stop switch I65 (Fig. 28); the button i controls the carriage feed switches I66, I61; the button 7' controls the carriage return switches I68, I69. and the button It controls the emergency stop switch I10.

Referring to the control set I6I, the button I controls the main switch III; the buttons m and 121. control the starting and stopping switches I12, I13, respectively, for the edge grinding motor 51-E; the buttons 12. and n control the starting and stopping switches I16 and I11 for the semifinish grinding wheel motor 51-C; the buttons 12 and 10' control the starting and stopping switches I18 and I19 for the rough grinding wheel motor 61-B; the buttons q and q control the starting and stopping switches I and IilI for the coolant pump motor I09, and buttons r and 1* control the high-low switches I82 for the speed control motor 86.

The carriage 4 at the end of its forward stroke is automatically stopped by striking and opening a stop switch I84, and it is likewise stopped at the end of its return stroke by striking and opening a feed circuit switch I85 (Fig. 2). A safety switch I86 is also connected with the carriage feed circuit in association with the work-gauge arm 31, so that when the arm is in full lowered position, as shown in Fig. 8, the switch will be I clamp them to the table surface.

engaged and held openby said arm. This prevents any feeding movement of the carriage from being started when the glass stop gauge is in glass-gauging position.

-across the outside lines L-l and L-3. The .ac-

tuating coils for the relays areindicated in the control circuits associated with the secondary of the transformer T and the relay contacts themselves are indicated as interposed between theseveral motor windings and the power lines ,L-l, 15-2 and L 3. The relay coils are designated with the same reference characters as tions.

In Figs. 2, 5 and 6, the machine is shown as.

equipped with a splash curtain 200 extending forward a distance from the forward front edge of the carriage 4 and extending vertically from a point some distance above the level of the work table to a point below the front top edge of thebase frame I. This curtain is suspended from a table 20! that extends from the forward front edge of the carriage 4 to beyond the forward end of the frame -I thence across the machine to the rear side of the frame around guide sheaves 2B2; thence to the opposite end of the frame and crosswise thereof around guide sheaves 203 supported by the housing 22, and thence to the rearward front edge of the carriage to which it is attached. The table is taut so that any movement of the carriage will move the cable and curtain therewith.

In the operation of the machine, one or more glass plates A are placed on the table I!) in successive order lengthwise of its inner edge with the plates projecting over said edge a distance permitted by the gauge pads 42, which, for such purpose, stand in the raised position shown in Fig. 8. When the gauge means'is in this position, the safety switch I86 in the operating circuit is held open by the arm 31 so that the control circuit is dead, and no operation of the carriage is permitted until the gauge means has been moved to inoperative position. The glass plates having been properly positioned on the table, the operator moves the control of the valve unit 25 to admit air under pressure to the upper ends of both cylinders 26 at the ends of the table, thus forcing the plungers 2|, rods 22 and work-clamping means l2 down and causing the separate blocks I! to be pressed into holding engagement with the glass plates to The yielding response of the blocks II to the applied pressure, due to the cushion means I9 between the parts It and I1, permits said blocks to adjust themselves to any unevenness in thickness of the glass plates and, therefore, to hold the under surface of the plates, with uniformly distributed pressure, flat to the table. The work having been clamped to the table in edge beveling position and the gauge means returned to its inoperative position, the motors 51 for the several grinding units and the pump motor I09 for the coolant system having been started, the control button 13 for the carriage feed is then pressed, causing the carriage to move forward on the frame I. During such forward stroke of the carriage, the rough grinding wheel 72-3 1 0 first engages and'travels-along the under surface of the projecting edge portion of the glass plates to befollowed by the semi-finishing wheel l2-C, the finishing wheel 12-D, andthe edging wheel l2-E, so that when the carria-ge 4 has completely traversed-its forward stroke of movement, the under side of the. projecting edge portion of the glass plate or plates will have been beveled to a smooth surface and theiextreme edge of the-plates rounded. This action gives a very fine finish tothe bevel surface, requiring a minimum of subsequent final "cleaning and dressing action. During this grinding action, the pressure applied thereby isagainst the. holding means I 2, which is sufficiently strong and rigid in its nature to absorbany vibration resulting from the grinding action. While, in the present instance, the glass plates are clamped to a subjacent flat surface and the grinding pressure is upward against such surface, it will be understood that the plates could be clamped to a superposed flat surface, in which event the grinding pressure would be on the upper side of the plate. In other words, the idea of the invention is to hold the plate to a flat surface by an opposed clamping means and to apply the beveling action to the side of the plates engaging the flat surface.

When the carriage reaches the 'end of its forward stroke, it engages the stop switch;l84 which opens the carriage operating circuit. The carriage is then returned to its normal .starting position by pressing the control button a which opens the return carriage operating circuit. When the carriage has returned to its initial starting position, it strikes and opens the stop switch I85. The driving of the carriage is through the lead screw 80, the speedof which, both for forward and rearward movementaiis .controlledby the buttons r and rin connection with the high-low switches I 82. .In this manner the carriage may be caused to haveeither a rapid or slow movement in either direction, as may be desired. Both motors 85 and 86 are used for rapid traverse, while one drives'and one controls for slow feeding movement.- The relationship of the grinding wheels to the work to suit the angle of bevel and the height of the work relative to the grindingv wheelsmay be nicely and accurately obtained by the adjustments permitted by the mounting of the unit blocks 5| on the bases 45 and the mounting of the grinding wheel head 19 on the respective blocks. Such adjustment is also facilitated by the inward and outward movements of the grinding units on the carriage.

We wish it understood that our invention is not limited to any specific construction, :arrangement or form of the parts, asit is capable of numerous modifications and changeswithout departing from the spirit of the claims.

Having thus described our invention, :what we claim as new, and desire to secure by United States Letters Patent,'is: I 1. In. a-machine of the class described, wherein a glass plate is held with an exposed edge, a carriage, means guiding said carriage for reciprocatory movements along said exposed edge in spaced relation thereto, a base member mounted on said carriage for adjustment transverse to its line of movement, a block carried by said base for tilting movement about a horizontal axis substantially parallel to said plate edge, a bearing head carried at the side of said block adjacent to said edge, means mounting said head on a side of the block adjacent to said edge for various adjustments relative to the block, a shaft journaled in substantially vertical position in said head, a bevel grinding member carried by said shaft for beveling engagement with the exposed plate edge as it passes therealong with the carriage, and means carried by said block and operable to drive said shaft.

2. An arrangement as called for in claim 1, wherein said shaft and operating means are in counterbalancing positions at opposite sides of said block and the operating means constitutes a motor that is mounted to the block on the opposite side thereof to said bearing head for vertical and swinging adjustment relative thereto, together with means mounting the drive means on the block for said adjustment.

3. In a machine of the class described, a fiat surface, means for clamping a glass plate to said surface with an exposed edge to be acted on projecting beyond an edge of said surface, stop means for the plate edge, means for moving said stop means into and out of stop engagement with such edge, an electric control circuit for the machine, and a normally closed switch in said circuit in the path of movement of said second and third means and operable thereby to open the circuit when the stop means is in plate edge engaging position.

4. In a machine of the class described having means for holding a glass plate with a projecting edge portion in position to be ground, and 'a carriage guided for movements lengthwise of said edge in spaced relation thereto, the combination of a grinding unit mounted on the carriage for movement therewith, said unit comprising a base mounted on the carriage for adjustment transverse to its line of movement, means operable to transversely adjust said base relative to the carriage, a block pivotally mounted on said base for tilting adjustment in a vertical plane parallel to the line of adjustment of the base and having a vertical face, means for locking said base and block in adjusted relation, a bearing head mounted on the vertical face of said block adjacent to said plate-holding means for both vertical and tilting adjustment relative to said block with the axis of tilting adjustment transverse to the tilting axis of the block, a shaft journaled in generally vertical position in said bearing head, a grinding wheel carried by said shaft in position to engage a projecting plate edge when the carriage is moved lengthwise thereof, and means carried by the block for driving said shaft.

5. In a machine of the class described having means for holding a glass plate with a project ing edge portion in position to be ground, and a carriage guided for movements lengthwise of said edge in spaced relation thereto, the combination of the grinding unit mounted on the carriage for movement therewith, said unit comprising a base mounted on the carriage for adjustment transverse to its line of movement, means operable to transversely adjust said base relative to the carriage, a block pivotally 12 mounted on said base for tilting adjustment in a vertical plane parallel to the line of adjustment of the base and having opposed vertical sides, means for locking said base and block in adjusted relation, a bearing head and an electric motor carried by said block on opposite vertical sides thereof with the grinding head adjacent to the plate-holding means for movement with the carriage lengthwise of the projecting edge of a plate held by said last means, means connecting the bearing head to the block for both vertical and tilting adjustment with the axis of tilting adjustment transverse to the tilting axis of said block, a shaft journaled in upright position in said head, a grinding wheel carried by said shaft in position to engage the projecting edge of a held plate, means connecting the motor to the block for adjustments similar to those of the bearing head, and means connecting and driving said shaft from said motor.

6. In a machine of the class described, a flat surface, means for clamping a glass plate to said surface with an edge'thereof projecting beyond an edge of the surface in position to be acted on, a rockshaft having its axis parallel to said edge,'plate edge engaging means carried by said shaft and movable into positions to serve as a stop gauge for said plate edge, an operating arm projecting from said shaft, means operable to grind a bevel onsaid projecting plate edge, an electric control circuit for said means, and a normally closed switch in said circuit in the path of movement of said arm actuated by the arm to open the circuit when said plate edge engaging means is in plate engaging position.

WILLIAM A. REASER. ELMER. A. ZIEMS. JOHN M. CHRISTMAN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 754,755 Edison Mar. 15, 1904 858,887 Millen July 2, 1907 937,912 Bailey Oct. 26, 1909 1,499,989 Lehmann July 1, 1924 1,664,713 Strickland Apr. 3, 1928 1,673,163 Schmelzkopf June 12, 1928 1,862,379 Koestlin June 7, 1932 1,896,533 Vuilleunier Feb. 7, 1933 1,906,739 Carruthers May 2, 1933 1,982,287 Einstein et al Nov. 27, 1934 2,031,743 Smith Feb. 25, 1936 2,040,466 Christy May 12, 1936 2,264,053 Russell Nov. 25, 1941 2,334,581 Pyne Nov. 16, 1943 2,347,283 Ross Apr. 25, 1944 2,435,059 Thompson Jan. 27, 1948 2,442,042 Hamilton Mar. 25, 1948 2,482,785 Lohutko Sept. 27, 1949 FOREIGN PATENTS Number Country Date 731,354 France May 30, 1932 

